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EPA’s Proposed CO2 Emissions Rule in Context

If you follow climate and energy news, you probably have or will encounter media regarding today’s proposed CO2 emissions rule by the EPA. Unfortunately, that media will probably not be clear about what the rule means in understandable terms. I’m writing this in an attempt to make the proposed rule more clear.

The graph above shows US CO2 emissions from energy consumption. This includes emissions from coal, oil, and natural gas. I have differentiated historical emissions in blue from 2013 EIA projections made in red, what today’s EPA proposal would mean for future emission levels, and low and high reductions prescribed by the Kyoto Protocol, which the US never ratified.

In 2011, historical US energy-related emissions totaled 5,481 million metric tons of CO2. For the most part, you can ignore the units and just concentrate on emission’s magnitude: 5,481. If the EPA’s proposed rule goes into effect and achieves what it sets out to achieve, 2020 emissions could be 4,498 MMT and 2030 emissions could be 4,198 MMT (see the two green triangles). Those 2030 emissions would be lower than any time since 1970 – a real achievement. It should be apparent by the other comparisons that this potential achievement isn’t earth shaking however.

Before I get further into that, compare the EPA-related emissions with the EIA’s projections out to 2030. These projections were made last year and are based on business as usual – i.e., no federal climate policy or EPA rule. Because energy utilities closed many of their dirtiest fossil fuel plants following the Great Recession due to their higher operating costs and the partial transfer from coal to natural gas, the EIA now projects emissions just above 2011’s and below the all-time peak. I read criticism of EIA projections this weekend (can’t find the piece now) that I think was too harsh. The EIA historically projected emissions in excess of reality. I don’t think their over-predictions are bad news or preclude their use in decision-making. If you know the predictions have a persistent bias, you can account for it.

So there is a measurable difference between EIA emission projections and what could happen if the EPA rule is enacted and effective. With regard to that latter characterization, how effective might the rule be?

If you compare the EPA emission reductions to the Kyoto reductions, it is obvious that the reductions are less than the minimum requirement to avoid significant future climate change. But first, it is important to realize an important difference between Kyoto and the EPA rule: the Kyoto pathways are based off 1990 emissions and the EPA is based off 2005 emissions. What happened between 1990 and 2005 in the real world? Emissions rose by 19% from 5,039 MMT to 5,997 MMT. The takeaway: emission reductions using 2005 as a baseline will result in higher final emissions than using a 1990 baseline.

If the US ratified and implemented Kyoto on the `Low` pathway (which didn’t happen), 2020 emissions would be 4,031 MMT (467 MMT less than EPA; 1445 MMT less than EIA) and 2050 emissions would be 2,520 MMT (no comparison with EPA so far). If the US implemented the `High` pathway, 2020 emissions would be 3,527 MMT (971 MMT less than EPA!; 1,949 MMT less than EIA!) and 2050 emissions would be drastically slashed to 1,008 MMT!

Since we didn’t implement the Kyoto Protocol, we will not even attain 2020 `Kyoto Low` emissions in 2030. Look at the graph again. Connect the last blue diamond to the first green triangle. Even though they’re the closest together, you can immediately see we have a lot of work to do to achieve even the EPA’s reduced emissions target. Here is some additional context: to keep 2100 global mean temperatures <2C, we have to achieve the lowest emissions pathway modeled by the IPCC for the Fifth Assessment Report (see blue line below):

Note the comment at the bottom of the graph: global CO2 emissions have to turn negative by 2070, following decades of declines. How will global emissions decline and turn negative if the US emits >3,000 MMT annually in 2050? The short answer is easy: they won’t. I want to combine my messages so far in this post: we have an enormous amount of work to reduce emissions to the EPA level. That level is well below Kyoto’s Low level, which would have required a lot of work in today’s historical terms. That work now lies in front of us if we really want to avoid >2C warming and other effects. I maintain that we will not reduce emissions commensurate with <2C warming. I think we will emit enough CO2 that our future will be along the RCP6.0 to RCP8.5 pathways seen above, or 3-5C warming and related effects.

Another important detail: the EPA’s proposed rule has a one-year comment period which will result in a final rule. States then have another year to implement individual plans to achieve their reductions (a good idea). The downside: the rule won’t go into effect until 2016 – only four years before the first goal. What happens if the first goal isn’t achieved? Will future EPA administrators reset the 2030 goal so it is more achievable (i.e., higher emissions)? Will lawsuits prevent rule implementation for years? There are many potential setbacks for implementing this rule. And it doesn’t achieve <2C warming, not even close.

3 thoughts on “EPA’s Proposed CO2 Emissions Rule in Context”

I wanted to add some additional context: these standards deal only with the energy sector. As seen below, the energy sector is currently the largest CO2 emitter, but this rule does nothing about the other sectors. This is one more reason why the effective result of the rule, if implemented on time and in full, will have little effect on overall US CO2 emissions: